What happens when subscribers mark your emails as spam?

Spam complaints affect your deliverability and, eventually, your sender reputation. Not all is lost though! Learn what feedback loops are and how they can help.

While it’s important to track positive metrics like opens, clicks and shares, email marketers must pay attention to negative ones too. Monitoring unsubscribes and spam complaints maximizes your chances of landing in the inbox.

Unsubscribes are easier to monitor as they feed back into your ESPs data management. Spam complaints are where things get a little bit more complicated.

What is a spam complaint?

A complaint is a result of a user clicking the ‘Spam’ button in their mailbox provider interface (be it mobile application, desktop software or webmail window).

Because this is a mailbox provider option rather than a part of the email (like the unsubscribe link), this information is not automatically fed back to the sender. In order to get it, you need to be part of a feedback loop.

What is a feedback loop?

Feedback loops (FBLs) are emails informing senders which of their users have complained about their email campaigns. They are delivered to a designated email address of your choice. Unfortunately, not all mailbox providers use them.

Which mailbox providers use FBLs?

The biggest ones are:

AOL

Hotmail

Yahoo

Comcast

Other FBLs:

Bluetie/Excite

Cox

Fastmail

Mail.ru

OpenSRS/Tucows

Rackspace (formerly Mailtrust)

RoadRunner/Time Warner Cable

Synacor

Terra

USA.NET

United Online/Juno/Netzero

Zoho.com

Gmail’s ‘not-quite’-feedback loop

Gmail has a slightly different feedback loop system, and it’s limited to a group of ESPs. How does it work? Rather than providing information on an email address basis, Gmail will send aggregate reports of a particular campaign that has performed badly.

What should you do?

If you are registered to receive feedback loops from mailbox providers, make sure the email addresses that complained are added to a suppression list (you should be able to make this process automatic). Otherwise, subsequent emails will arrive in the spam folder of the complainer and the more that happens, the more your sender reputation will suffer.

With Gmail, monitor your email performance levels closely and if you’re not getting the results you need, consult with your ESP. If they advise that spam complaints might be an issue, make your unsubscribe link more visible. It might sound counter-intuitive, but you’re much better off with losing subscribers than having them complain. Because either way, they are not engaging with your emails, so you’re not getting the return on your investment.

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